Tube forming apparatus



Sept. 4, 1962 D. N. JUDE'LSON TUBE FORMING APPARATUS 4 Sheets-Sheet 1 Filed Oct. 14, 1957 INVENTOR. DAV/D f/ JUDfZIfO/V Sept. 4, 1962 D. N. JUDELSON 3,052,197

TUBE FORMING APPARATUS Filed Oct 14, 1957 4 Sheets-Sheet 2 Sept. 4, 1962 D. N. JUDELSON TUBE FORMING APPARATUS 4 Sheets-Sheet 3 Filed Oct. 14, 1957 Sept. 4, 1962 D. N. JUDELSON 3,052,197

TUBE FORMING APPARATUS Filed Oct. 14, 1957 4 Sheets-Sheet 4 INVENTOR.

D4 V/D IV. JUDELSON BY Q 1 firm/Z75 United States Patent 3,052,197 TUBE FORMING APPARATUS David N. Jndelson, New York, N.Y., assignor to Oscar I. Judelshon, Inc., Jersey City, N.J., a corporation of New York Filed Oct. 14, 1957, Ser. No. 689,812 9 Claims. (Cl. 112-63) The present invention relates generally to sewing mechanisms, and in particular to improved apparatus for stitching a lengthof material into tubular form and rewinding the tube of material into a roll for further processing in the manufacture of bias cut tape.

Machines for stitching material into generally tubular form forsubsequent cutting on the bias fall generally into two categories. The first type of machine is arranged to handle material folded in half with its edges coextensive and stitches the adjacent side edges together at a location spaced inwardly from the coextensive edges, leaving a prescribed selvage which is opened up and flattened down outwardly .of the seam. The second type or category is arranged to handle material formed into tubular configuration with the edges adjacent and abutting, with provision for zig-zag stitching of the adjacent edges together to form the tube. The resultant tube of material formed on either category of machine is then cut on the bias to reorient the warp and weft threads thereof to a prescribed angle relative to the cut edges, for example, with bias-cutting apparatus of the type shown and described in my United States Patent No. 2,772,734 of December 4, 1956.

It is broadly an object of the present invention to provide improved tube-forming apparatus of the type in which the adjacent side edges are secured in abutment by siz-zag stitching whereby a fiat joint of a single thickness of the material is formed at the joined edges.

Typical zig-zag stitching apparatus for forming material into a tube incorporates a sewing machine carried on a base or support and having a head end spaced to one side of the support. A reciprocating needle bar carrying a needle, presser foot bar carrying a presser foot are mounted within the head end of the machine. Cooperating with this conventional stitching mechanism is a shuttle or bobbin of the rotary hook type which is adapted to cooperate with the needle of the stitching mechanisms to produce 'zig-zag stitching. In order to operate this type of apparatus, the shuttle and associated hook must be disposed within the extent of the tube of material and at a location beneath the needle. To achieve the drive for such bobbin or shuttle, the prior art devices have employed an auxiliary arm providing a housing in advance of the sewing machine which terminates at its forward end in a vertical or upstanding horn. Journaled in the horn is a vertical shaft which is coupled at one end to the drive for the sewing machine and at the other end to the shuttle or bobbin. By this arrangement, it is possible to advance the material in generally tubular form about the shuttle and its associated drive, with the opposite edges of the material uppermost and passing to opposite sides of the upstanding horn of the auxiliary arm. Since this horn is disposed in advance of the head end of the sewing machine, the material must be brought to the opposite sides thereof before being brought into abutment for zig-zag stitching by the cooperating needle and bobbin. The presence of the upstanding arm containing the shuttle drive along the stitch path or feed line obviously obstructs ready access to the stitching location and precludes unimpeded Inaterial travel in tube form. It is necessary for the operator to'first guide the material about the obstructing horn and then bring the opposite edges of the material into contiguou's relationship for stitching. In that the horn is quite close to the stitching location, it is necessary for the operator to guide the edges of the material into proper position'for stitching in a relatively short travel. As a practical matter such guiding is difficult and is complicated by the presence of the obstructing horn which obstructs the operator from reaching into the critical zone and maneuvering the material into position for stitching. Typical prior art apparatus of this type is illustrated in United States Patent No. 1,828,554 of October 20, 1931 to H. M. Bonker.

Broadly, it is an object of the present invention to provide improved tube-forming apparatus obviating one or more of the aforesaid difficulties. Specifically, it is within the contemplation of the present invention to provide an improved driving arrangement for the bobbin or shuttle of tube-forming apparatus enabling free and virtually unobstructed advance of the material in tubular form to the needle and bobbin for stitching.

In conventional tube-forming apparatus of the zigzag type, it is commonplace to employ a pair of rollers rearwardly of the cooperating needle and presser foot for intermittently advancing the material past the needle for zig-zag stitching. Subsequent thereto, means are provided for distending or flattening the stitched tube whereupon the flattened tube may be loosely folded in a box, or rewound in roll form. Diificulty is presented in attempting to rewind the stitched tube in a roll and accordingly commercial systems usually deposit the material in loosely folded condition in a box or bin.

It is a further object of the present invention to provide an improved rewind which enables the rewind of material in a tight roll.

It is a still further object of the present invention to provide an improved rewind for use with tube-forming apparatus which is arranged to intermittently advance or pull the material past the sewing mechanisms of the tubeforming apparatus and is capable of rewinding the material in rolled form with the tube distended and flattened.

It is a still further object of the invention to provide an improved rewind which may be coordinated to the operation of the sewing mechanisms of the tube-forming apparatus and is driven to take up the tube of material as the same passes through the sewing mechanisms.

In accordance with an illustrative embodiment demonstrating features of the present invention, the tube-forming apparatus incorporates a sewing machine which includes a support, a machine body extending to one side of the support and having a head end disposed along the material feed path of the machine, a needle mounted in the head end and adapted to be driven through a stitch-forming stroke, and a drive shaft operatively connected to the needle for driving the needle through the stitch-forming stroke. In advance of the machine body there is arranged an arm which extends to the one side of the support and substantially transverse to the feed path for the material. A feed bed and housing is carried on the arm and extends longitudinally and substantially along the feed path and supports a hook and bobbin mechanism beneath the head end of the sewing machine for cooperation with the needle to join opposite ends of the length of material in abutting relation by zig-zag stitching when advanced along the feed path. The arm carries appropriate means for forming the material into approximate tubular form for stitching by the sewing machine along adjacent edges. The forming means is arranged to orient edge adjacent portions of the material in approximate tubular form at different levels, one above the other, while the arm carries a driving connection for the hook and bobbin mechanisms which driv 'ing connection extends substantially horizontally and be tween the oriented end adjacent portions of the material in tubular form. The arrangement of the tube-forming means and the driving connection to the hook and bobbin mechanisms enables the operator to advance the material toward the stitching location with the edges slightly overlapped; and free access is had to stitching location for guiding the material in relation to the stitch-forming mechanisms.

As a further aspect of the invention, a rewind is disposed behind the sewing machine of the tube-forming apparatus and is arranged to intermittently advance the material through the sewing machine in timed relation to operation of the stitch-forming mechanisms. The rewind includes pulling rollers and a rewind shaft which is driven by a slip clutch connection to the pulling rollers whereby a uniform and tight roll may be formed on the rewind shaft as the diameter of the roll builds up. The pulling .rollers are driven by an improved coupling including a one-way clutch and speed reduction gearing coordinated to the drive of the sewing machine which speed reduction gearing serves to preclude overrunning of the pulling roll- .ers during intervals intermediate indexing and effectively isolates the slip clutch driven rewind shaft from the oneway clutch actuated from the sewing machine.

Advantageously, with tube-forming apparatus in accordance with the present invention, it is possible for material to be advanced past the sewing machine in approximate tubular form. Further, the material requires little or no orientation by the operator for the disposition of the opposite edges in proper position for stitching. Still further, the material may be flattened out and rewound into a tight, well defined roll which roll may be removed from the machine for further processing, for example, in accordance with the apparatus illustrated in my United States Patent No. 2,772,734.

The above brief description, as well as further objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of a presenting preferred embodiment, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a plan view of tube-forming apparatus in ac- .cordance with the present invention;

FIG. 2 is an enlarged fragmentary plan view, with parts broken away and sectioned, showing material in tubular form as it is advanced toward and pulled away from the stitching location;

FIG. 3 is an elevational view taken substantially along the line 3-3 of FIG. 1 and looking in the direction of the arrows, showing a guiding unit for forming the material into approximate U-shaped configuration; FIG. 4 is an elevational view taken substantially along the line 4-4 of FIG. 1 and looking in the direction of the arrows, showing a further guiding unit for bringing the material into generally circular configuration with edge adjacent portions disposed horizontally one above the other and overlapped;

FIG. 5 is a plan view, with the material removed, showing the sewing, tube-forming, and distending means embodied in the tube-forming apparatus of the present invention;

FIG. 6 is a sectional view taken substantially along the line 6-6 of FIG. 5 looking in the direction of the arrows;

FIG. 7 is a sectional View taken substantially along the line 7-7 of FIG. 5 and looking in the direction of the arrows;

FIG. 8 is an elevational view, with parts broken away, showing the improved rewind incorporated in the tube forming apparatus, the view being taken from the far side of the rewind as illustrated by the directional arrow 8 in FIG. 1;

FIG. 9 is a sectional view taken substantially along the line 9-9 of FIG. 1 looking in the direction of the arrows and showing the internal arrangement of the rewind; and,

FIG. 10 is a fragmentary plan view illustrating the slip clutch drive for the rewind shaft of the rewind.

Referring now specifically to the drawings, there is shown in FIG. 1 my improved forming apparatus, generally designated by the reference numeral 10, which is adapted to form a length of material M into a tube T in which the opposite side edge m m are joined in abutment zig-zag stitching S. The tube-forming apparatus 10 includes a material feed or supply 12 which is adapted to support the material either in roll form or in flat folds; a first material guiding unit 14 adapted to form the material M into generally U-shaped configuration; -asecond material guiding unit 16 which is adapted to form the material into a generally circular configuration with edge adjacent portions overlapped and substantially along the feed path P to the sewing machine; tube-forming, stitching and distending apparatus 18 which receives the mate- 'rial M in generally circular configuration from the material guiding unit 16 and stitched the same along the ad jacent abutting edges m m into a tube T and thereafter flatten the tube out into its full width with the stitched line S disposed medially thereof; and a rewind 20 which is arranged to pull the material through the apparatus 18 and is adapted to rewind the flattened stitched tube T in the form of a roll R.

The material feed supply 12 incorporates a stand 22, which in this illustrative form of the invention carries an unwind shaft 24 carrying the material in rolled form. The material M is passed over one or more tensioning bars, such as the bar 26, and is then fed in its full width toward the first material forming or guiding unit 14. In lieu of the material feed 12 which incorporates the un- Wind shaft 24 and is suited to carry the material in roll form, the material can be supported on a flat bed or base in folded condition for advance through the tensioning bars 26 toward tube-forming apparatus 10.

The first material guiding unit 14, which is illustrated in detail in FIG. 3, includes a frame 28 which carries a pair of guide members 30, 32 disposed one within the other. The guide members 30, 32 are dependingly supported from the horizontal cross bar 34 of the frame 28 and are each of generally U-shaped configuration whereby they cooperate to form a guideway which causes the material M to be formed into the illustrated configuration with the opposite side edges m my in a common horizontal plane and spaced from each other.

The material M in this generally U-shaped configuration is then advanced to the second material-forming or guiding unit 16, the details of which are illustrated in FIG. 4. The unit 16 incorporates an upright or standard 36 which carries first and second forming members,

respectively designated by the reference numerals 38, 40. The forming member 38- includes horizontally-extending supporting arms 38a, 38b adjustably mounted on the standard 36 and formed therebetween with a semi-circular forming section 380. The forming section 380 extends to one side of the vertical center plane (defined by the feed line or path P) of the machine 10 and issupported to the one side of said plane by provision of the reverse bends 38d, 38e. The second forming member 40 includes horizontally-extending supporting arms 40a, 40b adjustably mounted on the standard 36 and carrying a semi-circular forming section 400 which is disposed symmetrically of the forming section 380 but extends to the opposite side of the vertical center plane of the machine. As seen in FIG. 1, the forming member 40 is disposed behind the forming member 38 in the direction of the material travel. The semi-circular forming sections 380, 40c cooperate together to turn the material into circular configuration with the opposite side edges overlapped, as indicated by the reference numeral 42 in FIG. 4. The degree of overlap may be readily adjusted by changing the relative position of the forming members 38, 40 rela tive to each other. This is achieved in that the respective supporting arms 38a, 38b and 40a, 40b are adjustably relative to the standard 36. Cooperating with the forming members 38, 40 is a separating blade 44 which is likewise adjustably carried by the standard 36, and is arranged to extend between the overlapped edges adjacent portions in the region 42-. It will be appreciated that the forming or guiding unit 16 brings the material approximately into the required circular configuration for stitching in the sewing machine, as will now be described.

Specific reference will now be made to FIGS. 2, 5, 6 and 7 wherein the details of the guiding, stitching and distending apparatus 18 are illustrated. By way of review, the apparatus 18 serves to stitch the edges m m in abutment by a line of zig-zag stitching S, the tube thereafter being distended to its full width for delivery to the rewind, as will be subsequently described. The apparatus 18 includes a support 46 having a top 46a at approximately table height. The support 46 carries a machine body 48 which extends to one side of the support and terminates in the head end 48a disposed along the ma terial feed and stitch path P Mounted within the head end 48a of the sewing machine is a needle 50 which is carried on a needle foot bar in the conventional fashion and is driven through a stitch forming stroke by a drive shaft 52. Cooperating with the needle is a presser foot 54 which is supported on a presser foot bar. The mechanisms carried within the sewing machine body or housing 48 are entirely conventional and accordingly will not be described in detail. The machine body or housing 48 is carried on a supporting casting 56 which extends along the one side of the support 46 and terminates at its forward end in a transversely-extending cantilevered arm 58. The arm extends generally parallel to the machine body 48 and terminates beyond the material feed or stitching path P which lies within the vertical center plane of symmetry of the machine. Supported on the cantilevered arm 58 is a combined feed bed and housing 60 which extends generally along the material feed and stitching path P and terminates at a location beneath the head end 4811 of the machine body 48. The housing 60 may be part of a single casting with the cantilevered arm 58 and the supporting casting 56 and includes a removable top plate or cover 62 allowing for access to the hollow interior 64 of the housing 60. The cover 62 is supported on the upright walls 6%, 60b of the casting 60 and extends beneath the needle 59 and the presser foot 54 to provide a throat plate section 62a for the sewing machine. Beneath the needle and below the throat plate section 62a is a conventional shuttle mechanism 64 which incorporates a hook and bobbin adapted to cooperate with the needle 50 to form the zigzag stitching S. The shuttle mechanism is supported on a shuttle shaft 66 which is journaled lengthwise of the housing 60 in bearings provided in the upstanding wall 60a, 60b. The shuttle 64 and its shaft 66 are driven from the main drive shaft 52 of the sewing machine for operation in appropriate timed relation by a coupling which includes an operative connection extending through the arm 58. This coupling embodies a gear and chain drive which includes a chain 68, a driving chain gear 70 on the drive shaft 52 of the sewing machine, and a driven chain gear 72 disposed in substantial alignment with the center line of transverselyextending arm 58 of the suppporting casting 56. Journaled lengthwise within the cantilevered arm 58 is a connecting shaft 74 which is supported adjacent one end by a hearing 76 in the casting 56 and at the other end in the bearing 78 on the outer wall 60c of the housing 60. The connecting shaft 74 carries the driven chain' gear 72 and accordingly is driven by the drive shaft 52 of the machine which is connected w'a a chain and gear connection 80 to the drive motor 82. An appropriate gear train is provided between the connecting shaft 74 and the shuttle shaft 66 for driving the latter. This gear train includes a spur gear 84 adjacent the outermost end of the connecting shaft '74 which is in meshing engagement with an idler spur gear 86. Integral with the spur gear 86 is a bevel gear 88 which is in meshing engagement with a bevel gear 90 on the rearmost end of the shuttle shaft 66. It will be appreciated that the coordinated drive to the shuttle mechanisms 64 includes the following: the chain gears 70, 72 interconnected by the chain 68, the connecting shaft 74 extending along the length of the cantilevered arm 58, the interengaging spur gears 84, 86, and the interengaging bevel gears =88, 90.

The cantilevered arm 58, as seen best in FIG. 7, provides a support having a comparatively small vertical dimension which carries the housing 60 along the material feed path P of the machine. The cross section of the arm 58 is made large enough to support the housing 60, but may be comparatively thin in that the only part housed therein is the connecting shaft 74. Accordingly, as will now be described, it is possible to advance the material M toward the stitching location at the cooperating needle 50 and shuttle 64 with the material substantially in the ultimate circular configuration which the tube must occupy as it passes through the stitching zone.

The housing 61 carries tube forming and distending means which include forming plates 92, 94 which extend transversely of the machine and spreading or distending members 96, 98 which extend lengthwise of the machine and are supported on the plates 92, 94. The forming plates 92, 94 are movably mounted on a bracket 100 fixed to the foremost end of the housing for adjustment toward and away from each other and into various positions symmetrically disposed in relation to the vertical center plane P of the machine. As seen in FIGS. 6 and 7, the forming plate 92 carries a horizontally-extending mounting arm 102 which is received within a guide slot 104 formed in the bracket 100. Similarly, the forming plate 94 has a horizontally extending arm 106 which is received within a guide slot 108 formed in the bracket 100. Thus it is possible to adjust the plates 92, 94 toward and away from each other by sliding the respective arms 162, 106 back and forth within the accommodating guide slots 104, 108. A lock bolt 110 is carried on the bracket 100 (see FIG. 6) and includes a locking plate 112 which may be brought into bearing engagement with the respective arms 102, 106 to lock the same in any position of lateral adjustment. The forming plates 92, 94 engage the tube of material internally to provide an inside mandrel and cooperate with the guide 16 which engages the material at the outside. The guide 16 is adjacent to and in advance of the forming plates 92, 94 and holds the material in a required configuration, for purposes to be subsequently described.

The spreading members 96, 98 are pivotally mounted on the forming plates 92, 94 by pairs of hinges 114, 116 for swinging movement toward and away from. each other and with respect to the vertical center plane of the machine. The spreading members 96, 98 are curved in cross section and progressively diminish in vertical extent from their leading ends 96a, 98a to their trailing ends 96b, 93b. At the leading ends 96a, 98a, the spreading members have a cross section generally coextensive with the cross section of the adjacent forming members 92, 94. At their trailing ends 96b, 98b, the spreading members are of minimum vertical extent and are spaced apart in an amount sufficient to distend the formed tube T to almost its full width for rewind.

The spreading members 96, 98 are supported and urged apart through the provision of a spring biased internal spider, generally designated by the reference numeral 118, which incorporates an elongated spider housing 120 which slidably accommodates a rod 122 carrying a mounting head 124. The head 124 supports a depending stud 125 which pivotally mounts connecting links 126, 128 having their outer extremities pivotally connected to the spreading members 96, 98. The slidable rod 122 extends at its rearmost ends beyond the spider housing 120 and carries thereon a knob 13%. Connected between the knob 130 and the fixed bracket 100 is a biasing spring 132 which tends to urge the rod 122 to the left in the showing of FIGS. 5 and 6 and in a direction tending to spread the members 96, 98 relative to each other. The spreading members 96, 98 may be brought together when the material is being inserted over the mandrel 7 formed thereby by pulling on the knob or grip 130 against the biasing effect of the spring 132, that is to the right in FIGS. and 6, whereby the head 124 translates toward the right carrying the links 126, .128 and associated spreading members. 96, 98 closer together.

-'The cantilevered arm 58, the housing 60, and the spreading and forming members 96, 98 are arranged in relation to each other to allow for the substantial free and unimpeded flow of the material M fromthe external and internal formers 16 and 92, 94 toward the stitching location. To this end, the cantilevered arm 58 is formed with a step 134 intermediate its ends and extending lengthwise in substantial alignment with the feed path or stitched line P to the sewing machine. The region of the supporting arm 58 outwardly of the step or shoulder 134 provides a substantially horizontal guide ledge 136 for the portion of the material M adjacent the edge m The horizontal guide ledge 134 is disposed at substantially the same level that this edge-adjacent portion occupies as it comes from the forming or guiding unit 16. The shoulder or step 134, which extends substantially along the stitch line P, assures that the edge m will be brought toward the stitching location substantially in position for stitching and requiring but minor orientation. As seen in FIG. 7, the curvature of the forming plate 92 is selected so that the material adjacent the edge m may readily enter into the guide ledge 136 with the edge m against the shoulder 134.

The inner wall 60d of the housing 68 is formed with a guide ledge 138 which extends inwardly from the inner side wall 60d toward and beyond the vertical center plane P of the machine (see FIG. 7). The guide ledge 138 is spaced below the level of the guide ledge 136, the spacing being selected to provide adequate clearance therebetween for the connecting shaft 74 of the shuttle drive. The guide ledge 138 is substantially at the same level as the cover plate 62 which serves as the bed for the sewing machine (see FIG. 6). The guide ledge 138 terminates at its inner side in a step or shoulder 140 which is positioned slightly outwardly of the vertical center plane P of the machine. 71" he degree of overlap between the edgeadjacent portions of the material as they pass beneath and over the connecting shaft 74 is of course determined by the position of the stops or flanges 134, 140 with respect to the vertical center plane of the machine. It has been found that a small degree of overlap is useful in that that operator can more easily spread the material M apart in the final short travel to the sewing head 48a, as compared to systems wherein the edges must be brought into abutment from a spread-apart position in this very short travel. As seen in FIG. 7, the spreading and forming member 98 has an appropriate vertical extent to enable the material adjacent the edge m to enter and occupy the guideway formed by the ledge 138 and the flange 140. It will be appreciated that the portion of the material adjacent the edge m travels at generally the same level until the material passes over the location of the connecting shaft 74 whereupon this portion is brought down' to the lever of the feed bed 62, while the portion of the material adjacent the edge m is brought down to the level of the feed bed 62 in advance of the cantilevered arm 58, travels beneath the connecting shaft 74 along the guide 138, 140, and thence on to the feed bed 62. After the material leaves the respective horizontal guides there is virtually nothing to obstruct its free flow toward the stitching location at the head end 48a of the machine body 48. As the material travels toward the stitching location, there is a slight degree of overlap due to the relative positions of the guides which direct the same over and beneath the driving connection for the shuttle mechanism (see FIG. 2).

Immediately in advance of the stitching location is a thin upstanding wedge 142 which is disposed in the vertical center plane of the machine. The wedge 142 separates the overlapped edges m m to bring the same into abutment for stitching by the big-zag stitching unit, as is well understood.

Specific reference Will now be made to FIGS. 1 and 8 to 10 inclusive for the details of the construction of my improved rewind 20. The rewind 20 includes upper and lower pulling rollers 144, 146 which extend between the opposite sides 148, 149 of the supporting frame. The rollers 144, 146 are carried one above the other on supporting shafts 150, 152 which extend between opposite sides 148, 149 of the supporting frame and are journaled therein by appropriate bearing.

Positioned rearwardly of the pulling rollers 144, 146 is a rewind shaft 154 which is adapted to carry a core 156 of cardboard or the like on which the stitched tube of material may rewind in the form of a roll R. The rewind shaft 154 is likewise journaled on appropriate bearings in the opposite sides 148, 149 of the frame.

The rewind shaft 154 is driven by the upper pulling roller 144. .The driving connection to the rewind shaft 154 includes a slip clutch 158 connected via a chain 160 to a sprocket 162 carried on the adjacent end of the sup porting shaft 150. As seen best in FIGS. 1 and 10, the slip clutch 158 includes a shaft 164 which is integral with or is a continuation of the rewind shaft 154. Keyed to the shaft 164 is the driven clutch plate 166 of the slip clutch, which driven plate is selectively urged into contact with the driving plate 168 which is loosely journaled on the shaft 164. The driving plate 168 is fixed to a sprocket 170 which is in engagement with the chain drive 160 connected to the sprocket 162. Surrounding the shaft 164 and outwardly of the driven clutch plate 166 is a spring 172 which bears at one end against the driven clutch plate 166 and at the other end against a stop collar 174 and a stop nut 176. By adjusting the tension of the spring 172, the driven clutch plate 166 may be urged against the driving clutch plate 168 with more or less pressure to control the degree of slip between the plates 166, 168. As is Well understood when the diameter of the roll R begins to build up, the clutch 158 begins to slip in increasing amounts to establish a substantially constant speed rewind. The setting of the slip clutch rewind, as will be described hereinafter, determines the tightness of the rewinding roll.

In order to facilitate threading, the top pulling roller 144 is movable away from the bottom pulling roller 146. To this end, and as seen best in FIG. 8, a lifting member 178 is rockably mounted on the supporting shaft 152 for the bottom roller 146. The lifting member 178 is formed with a camming surface 178 having a development selected to progressively raise the supporting shaft 150 to separate the peripheries of the rollers 144, 146 in response to movement of the lifting member. The lifting member 178 is manipulated by a handle 180 which may be depressed, as seen in FIG. 8 to translate the lifting member 178 in a counter-clockwise direction and into engagement with the adjacent overlying end of the supporting shaft 150. To facilitate such up and down movement of the roller 144 it is of course necessary to journal the opposite ends thereof in vertical guideways formed in the upright supports 148, 149. Only a slight separation between the pulling rollers 144, 146 is required to facilitate the threading of the flattened tube therebetween for rewind, as seen in FIG. 9.

In order to assure appropriate tension on the driving chain 160 which connects the sprockets 162, 170, a Weighted idler sprocket 182 is pivotally supported at the end of an arm 184 in engagement with the chain 160.

. One of the pulling rollers 144, 146 is driven from the drive shaft 52 of the sewing machine to effect intermittent advance of the material through the unit 18 in timed relation to operation of the zig-zag stitching mechanisms. In this illustrative form of the invention, the drive shaft 52 is coupled to the supporting shaft 152 for the bottom pulling roller 146. The coupling includes a onewayclutch 188, an eccentric drive 196 for the one-way clutch 188, and speed-reduction worm gearing 192 connecting the output of the one-way clutch 138 to the bottom pulling roller 1-46. Specifically, the drive shaft 52 carries a driving sprocket 193 which is connected via the chain 194 to a driven sprocket 196 of an eccentric 190. The eccentric is suitably journaled on a supporting bracket 200 fixed to the forward side of the supporting frame 148, 149. The eccentric 190 is of the adjustable type and includes a slide block 202 which may be brought to various adjusted positions radially in its accommodating slot 204 by an adjustment screw 296. Secured to the adjustable eccentric block 202 via the pivotal connection 208 is the eccentric arm 210 which is pivotally connected at 212 to the driving member 214 of the one-way or ball clutch 188. The output shaft 216 of the one-way clutch 188 carries a large diameter gear 218 which is connected to the smaller diameter input gear 220 of the speed-reduction unit 192. The speed-reduction Worm gearing 192, the internal arrangement and details of which are well understood, is adapted to provide a speed step down with a corresponding increase in torque. The output shaft 222 of the speed-reduction gearing carries a driving sprocket 224 which is connected via a chain 226 to a driven sprocket 228 which is connected to the supporting shaft 152 of the lower pulling roller 146.

During each cycle of rotation of the drive shaft 52 of the sewing machine, a prescribed motion is imparted to the eccentric arm 210 to provide input to the one-way clutch 188. For each such motion, the output shaft 216 of the one-way clutch is indexed through a prescribed are, which are is a function of the stroke imparted to the arm 210 and of the setting of the adjustable eccentric 198. The gearing 218, 220 is of the order of a five-to-one step down whereby it is possible to translate a rather small stroke at the eccentric arm 210 into an appreciable input to the speed-reduction unit 192. By the use of the gearing 218, 220 it is possible to have a minimum index distance for the arm 210 which reduces inertial forces. By employing a speed reduction in the unit 192 of the order of 75 to 1, any errors which may be introduced from the indexing drive are divided by the speed reduction factor. It is thus possible to obtain very accurate indexing of the pulling rollers 144, 146 as a function of the drive of the shaft 52. Apart from the fact that the speed-reduction unit 192 reduces the error by a very substantial factor, its use precludes the necessity of the intermittently-indexed clutch 188 carrying the large load that is required to operate the pulling rollers 144, 146. Further in that the pulling rollers 144, 146 have a tendency to overtravel in the same direction as the driving direction of the clutch 188, the interposed speed reduction unit 192 precludes the transmission of any overrunning forces from the pulling rollers 144, 146 back to the clutch 188. Still further, with the slip driven rewind shaft 154, a load must be provided against which the rewind drive may slip. In the absence of the speed-reduction unit 192, it will be necessary to provide some load, (i.e. on the pulling rollers), against which the clutch 158 could slip for achieving tight rewind. Thus the intermeshing worm gears of the speed-reduction unit 192 effectively isolate the pulling and rewind system from the indexing clutch 188, and make it possible to have the clutch 158 slip, and precludes back transmission from the pulling rewind system to the indexing clutch 188. My improved mechanisms for coordinating the rewind to the sewing machine is capable of accurately translating the drive of the sewing machine into corresponding incremental indexings of the pulling rollers 144, 146 in adjusted and timed relation to the stitch-forming action at the sewing machine.

Disposed rearwardly of the head end 48a of the sewing machine body 48 are a pair of auxiliary pulling rollers 230, 232 which are adapted to engage the seamed tube along the stitch line S immediately behind the needle 50 and the presser foot 54. The upper auxiliary pulling roller 230 is driven in timed relation to operation of the pulling rollers 144, 146. The lower auxiliary pulling roller 232 is journaled as an idler on a bracket 234 fixed to the housing 120. The roller 230 is supported on a shaft 236 which extends into a housing 238 rockably mounted on pivots to 2-40. The housing turned on the pivots 240 about an axis parallel to the stitch line P whereby the upper auxiliary pulling roller 230 may be rocked away from the idler roller 232 to enable the insertion of the tube there-beneath. The upper auxiliary pulling roller 230 is urged against the idler roller 232 by springs 242 which bear against the housing 238 on the side remote from the pivots 240. Such spring bias causes the supporting shaft 236 to be rocked downwardly thereby urging the roller 230 against the roller 232. The upper auxiliary roller 230 is driven from a shaft 236 Which carries a sprocket 244 connected by a chain 246 to a further sprocket 248 fixed to the driven sprocket 228 for the lower pulling roller 146. Accordingly, the auxiliary pulling rollers 230, 232 are driven in tandem with the main pulling rollers 144, 146.

What I claim is:

l. Tube-forming apparatus comprising a support, a sewing machine including a machine =body extending to one side of said support and having a head end disposed along a material feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitch-forming stroke, a drive operatively connected to said needle for driving the same through said stitch-forming stroke, an arm operatively connected to said support in advance of said machine body and extending substantially transverse to said feed path to said sewing machine, a housing carried by said arm and extending substantially along said feed path, hook and bobbin means within said housing and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, means for coupling said hook and bobbin means to said drive including a connecting shaft extending within said arm, and forming means in advance of said sewing machine including guides adapted to direct edge-adjacent portions of said material over and under said connecting shaft and spreader members adapted to direct said material in the form of a tube about said housing whereby the tube may be brought to the cooperating needle and hook and bobbin means of said sewing machine for stitching, said spreader members extending rearwardly of said sewing machine and being of gradually diminishing vertical extent whereby the stitched tube may be distended and flattened.

2. Tube-forming apparatus comprising a support, a sewing machine including a machine body extending to one side of said support and having a head end disposed along a material feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitch-forming stroke, a drive operatively connected to said needle for driving the same through said stitch-forming stroke, an arm operatively connected to said support in advance of said machine body and extending substantially transverse to said feed path to said sewing machine, a housing carried by said arm and extending substantially along said feed path, hook and bobbin means within said housing and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, and means for coupling said hook and bobbin means to said drive including a driving connection extending within said arm, forming means on said arm and housing in advance of said sewing machine including substantially horizontal edge-aligning guides disposed in vertical spaced relation and adapted to direct edge-adjacent portions of said material over and under said driving connection.

3. Tube-forming apparatus comprising a support, a sewing machine including a machine body extending to one side of said support and having a head end disposed along a material feed path to said machine, a reciprocat ing needle mounted in said head end and adapted to be driven through a stitch-forming stroke, a drive operatively connected to said needle for driving the same through said stitch-forming stroke, an arm operatively connected to said support in advance of said sewing machine, a housing carried by said arm and extending substantially along said feed path, hook and bobbin means within said housing and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, means within said housing and arm for coupling said hook and bobbin means to said drive including a substantially horizontal connecting shaft extending within siad arm, material guide means in advance of said sewing machine including substantially horizontal guides having substantially vertical edge-aligning portions adapted to direct edge-adjacent portions of said material over and under said connecting shaft in overlapping relation, and material advancing means for advancing said material to said cooperating needle and hook and bobbin means for joining the adjacent edges of said material to form a tubing.

4. Tube-forming apparatus comprising a support, a sewing machine including a machine body extending to one side of said support and having a head end disposed along a material feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitchforming stroke, a drive operatively connected to said needle for driving the same through said stitch-forming stroke, an arm operatively connected to said support in advance of said machine body and extending substantially transverse to said feed path to said sewing machine, a housing carried by said arm and extending substantially along said feed path and providing a work surface, hook and bobbin means within said housing and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, means for coupling said hook and bobbin means to said drive including a connecting shaft extending within said arm, material guide means in advance of said sewing machine including guides adapted to direct edgeadjacent portions of said material over and under said connecting shaft in overlapping relation and on said work surface, and a parting member in alignment with and in advance of said needle and carried by said housing for bringing said edges in substantial abutment for joining together by the cooperating needle and hook and bobbin means.

5. Tube-forming apparatus comprising a support, a sewing machine including a machine body extending to one side of said support and having a head end disposed along a material feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitchforming stroke, a drive operatively connected to said needle for driving the same through said stitch-forming stroke, an arm operatively connected to said support in advance of said machine body, a housing carried by said arm and extending substantially along said feed path, hook and bobbin means within said housing and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, means for coupling said hook and bobbin means to said drive including a connecting shaft extending within said arm, guide means adapted to direct one longitudinal edge of said material over said connecting shaft and the other longitudinal edge of said material under said connecting shaft and into overlapping relation, and a parting member in alignment with and in advance of said needle for bringing said edges in substantial abutment for joining together by the cooperating needle and hook and bobbin means.

6. An apparatus for forming a tube from a length of material comprising a support, a sewing machine head mounted thereon including a stitch-forming needle positioned along a feed path, an arm extending from said support substantially transverse to said feed path, a housing carried by said arm extending along said feed path and below said sewing machine head and providing an upwardly facing work surface, bobbin means within said housing positioned to cooperate with said stitch-forming needle, drive means operatively connected to said stitchforrning needle and said bobbin means, said drive means extending through said arm and said housing to said bobbin means, and guide means to form said material into tubular form including a first edge guiding means for guiding one longitudinal edge of said length of material over said arm and onto said upwardly facing work surface and a second edge guiding means for guiding the other longitudinal edge of said length of material under said arm and onto said upwardly facing work surface into a prescribed relationship to be joined together by said stitch-forming needle and cooperating bobbin.

7. An apparatus for forming a tube from a length of material comprising a support, a sewing machine head mounted thereon including a stitch-forming needle positioned along a feed path, an arm extending from said support substantially transverse to said feed path, a housing carried by said arm extending along said feed path and below said sewing machine head and providing an upwardly facing work surface, bobbin means within said housing positioned to cooperate with said stitch-forming needle, drive means operatively connected to said stitchforming needle and said bobbin means, said drive means including a drive shaft extending through said arm and means connecting said drive shaft to said bobbin means, and guide means to form said material into tubular form including a first edge guiding means for guiding a first longitudinal edge of said length of material over said arm and drive shaft and onto said upwardly facing work surface and a second edge guiding means for guiding the other longitudinal edge of said length of material under said arm and drive shaft and onto said upwardly facing work surface into a prescribed adjoining relationship to be joined together 'by said stitch-forming needle and cooperating bobbin.

8. In combination, a sewing machine including a support, a machine body extending to one side of said support and having a head end disposed along a material feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitch-forming stroke, a drive shaft operatively connected to said needle for driving same through said stitch-forming stroke, an arm extending to said one side of said support in advance of said machine body and extending substantially transverse to said feed path to said sewing machine, a feed bed and housing carried by said arm and extending longitudinally and substantially along said feed path, bobbin means within said housing beneath said head end and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, coupling means interconnecting said drive shaft and said bobbin means extending within said transverse arm, and means carried by said arm for forming said material into approximate tubular form for stitching by said sewing machine along adjacent edges, said forming means including forming parts having guides at two different levels for guiding opposite and edge-adjacent portions of said material over and under respectively said coupling means within said arm, said guides being disposed substantially along said material feed path and directed toward said head end of said machine body for guiding said length of material toward said sewing machine, said forming means further including adjustable spreading members carried on said housing and extending rearwardly of said sewing machine for distending the stitched tube.

9. In combination, a sewing machine including a support, a machine body extending to one side of said support and having a head end disposed along a material 13 feed path to said machine, a needle mounted in said head end and adapted to be driven through a stitch-forming stroke, a drive shaft operatively connected to said needle for driving the same through said stitch-forming stroke, an arm extending to said one side of said support in advance of said machine body and extending, substantially transverse to said feed path to said sewing machine, a feed bed and housing carried by said arm and extending longitudinally and substantially along said feed path, bobbin means within said housing beneath said head end and cooperating with said needle for joining opposite edges of a length of material in abutting relation when advanced along said feed path, coupling means interconnecting said drive shaft and said bobbin means extending within said transverse arm, and means carried by said arm for forming said material into approximate tubular form for stitching by said sewing machine along adjacent edges, said forming means including forming parts having guides at two different levels for guiding opposite and edge-adjacent portions of said material over 20 and under respectively said coupling means within said arm, said guides being disposed substantially along said material feed path and directed toward said head end of 14- said machine body for guiding, said length of material toward said sewing machine.

References Cited in the file of this patent UNITED STATES PATENTS 146,948 Richardson Ian. 27, 1874 978,481 Pelharn Dec. 13, 1910 1,828,554 Bunker Oct. 20, 1931 2,256,746 Mayer Sept. 23, 1941 2,347,901 Gardner et a1 May 2, 1944 2,406,677 Gardner et a1, Aug. 27, 1946 2,415,824 Katz et a1. Feb. 18, 1947 2,526,022 Ger-stein et a1. Oct. 17, 1950 2,529,575 Sailer Nov. 14, 1950 2,534,015 Gerstein et a1 Dec. 12, 1950 2,585,762 Gardner Feb. 12, 1952 2,845,232 Johnson et a1. July 29, 1958 FOREIGN PATENTS 443,855 Germany May 9, 1927 378,157 Great Britain Aug. 11, 1932 401,101 Great Britain Nov. 9, 1933 

